Lock for show-cases.



M. KURTZON. LOCK FOR SHOW CASES. APPLICATION FILED DEG.8, 1911.

1,017,978. Patented F eb.20,"1912.-

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m1m I COLUMBIA PLANoaRAPH CO, WASHINGTON. D. c.

UNITED STATES PATENT OFFICE.

MORRIS KURTZON, OF CHICAGO, ILLINOIS.

LOCK FOR SHOW-CASES.

To all whom 'it may concern:

Be it known that I, MORRIS KURTzoN, citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Locks for Show-Cases,

of which the following is aspecification.

This invention relates to improvements in looks of the type especially adapted to serve as locking means for show cases where the doors slide either horizontally or vertically in frames in which suitable keepers are provided.

The especial object of my invention is to provide a lock made up of few parts of strong and cheap construction so designed as not to get out of order or become displaced with ordinary use.

In the accompanying drawing in which I have shown a preferred embodiment of my invention the parts are represented about twice the normal size in order to bring out clearly all details of construction.

In said drawing :-Figure 1 is a view in side elevation of a showcase lock constructed according to my invent-ion, in which the rear plate is shown in section and partly removed; Fig. 2 is a rear elevation of my improved lock with the rear plate removed; and Fig. 3 is a side elevation of the look from the opposite side of Fig. 1.

Referring to the details of the drawing, 7 represents the face plate of the lock upon which the operating parts are mounted.

1 This plate is provided with suitable screwholes '7 near its upper and lower ends with a bolt opening 7 and projecting rearwardly therefrom are integral posts or studs 8, 9, 10 and 11. The post 8 is slotted vertically as at 8 and has a pin 8 extending transversely through it upon which is pivotally mounted the locking arm 12 on the upper end of which is the bolt 12 and at the lower end is a lug 12 The post 9 is integral with the post 8 and is tapped to receive one of the screws by which the rear plate 16 is attached to the base plate 7 In addition to receiving one of the rear plate attaching screws, the post 10 has coiled about it a wire spring 13 the upper end of which is attached to the stud 11, and the lower end bears against the upper end of the projecting arm 14 of the pawl 14. This pawl is pivotally mounted at its upper end on the stud 10 from which it hangs pendant, and at its lower end is formed with a rounded nose Specification of Letters Patent.

Application filed December 8, 1911.

Patented Feb. 20, 1912.

Serial No. 664,640.

14", while the lower portion of the arm 14 is beveled as at 14 and is pointed at its extremity as at 14 The lower portion of the pawl 14 rides upon and engages acylinder 15 which is rotatably mounted at one end in the plate 7, and is supported at its opposite end in the tubular extension 16 of the rear plate 16. The cylinder 15 has helically formed threads 15 on the portion of its surface next the plate, and between some of these threads, pins 15*, 15, extend radially from opposite sides of the cylinder 15. One of the threads 15 is mutilated as shown at 15 (Fig. 3) leaving a shoulder 15 which forms a stop for the pointed end 14 of the pawl 14 when the cylinder is rotated so as to bring said parts in juxtaposition. The cylinder is longitudinally slotted as at 15 to form a keyway to which access is had through the opening 16 in the barrel 16 of the plate 16, for a suitablekey for turning the cylinder 15 in its bearings.

It will be understood that the tension of the spring 13 holds the pawl 14 in frictional engagement with the cylinder 15, and the spaced relation between said pawl and its extension 14 is such, that the former rides in the grooves'between the threads, while the latter rides upon the periphery of the threads, as the cylinder is turned. The lug 12 at the lower end of the arm 12 extends between the threads 15 hence the rotation of the cylinder 15 will cause said end to move longitudinally of said cylinder and thus project and retract the bolt 12, depending upon the direction in which said cylinder is turned. The pins 15, 15, project radially from the cylinder between the threads and thus are positioned in the path of the lug 12 and serve as stops to limit the movement of the arm 12 in its locking and unlocking movements.

The engagement of the end 14 of the ex tension 14 with the shoulder 15 serves to lock the cylinder against rotation in one direction hence the bolt 12 cannot be retracted or moved to its disengaged position until the extension is lifted out of the path of the shoulder, which is done by any key which will push outwardly the lower end of the pawl 14.

From the construction described, it will be seen that my improved lock comprises but three moving parts, 2'. e. the locking lever or arm 12, the cylinder 15 and the pawl 14, and that there is no strain on the spring from efforts to force the look, as the function of the spring 13 is merely to hold the pawl in frictional engagement with the cylinder.

Having thus described my invention what I claim as new, is

1. In a lock, supporting face and back plates, a locking arm pivotally mounted on said face plate, a worm rotatably mounted in said plates and engaged by the locking arm, a pawl pivotally mounted on said face plate and normally engaging said worm, means for limiting the movement of said locking arm on said worm, and means on said worm adapted to engage said pawl to limit the rotating of said worm.

2. In a lock, supporting face and back plates, a locking arm pivotally mounted to move at right angles to said face plate and carrying a bolt adapted to be projected through a suitable opening in the face plate, 2(

a worm rotatably mounted in said plates, engaged by said locking arm, and having a key-way formed therein, a pawl pivotally and yieldingly mounted on said face plate and normally engaging said worm, means on 2E In testimony whereof I atfix my signature 3G in the presence of two witnesses.

MORRIS KURTZON. Htnesses R. A. FosTER, O. H. MOORE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

